Pesticide found in milk decades ago may be associated with signs of Parkinson’s

 

Source:

American Academy of Neurology (AAN)

Summary:

A pesticide used prior to the early 1980s and found in milk at that time may be associated with signs of Parkinson's disease in the brain, according to a new study.

"The link between dairy products and Parkinson's disease has been found in other studies," said study author R. D. Abbott, PhD, with the Shiga University of Medical Science in Otsu, Japan. "Our study looked specifically at milk and the signs of Parkinson's in the brain."

For the study, 449 Japanese-American men with an average age of 54 who participated in the Honolulu-Asia Aging Study were followed for more than 30 years and until death, after which autopsies were performed. Tests looked at whether participants had lost brain cells in the substantia nigra area of the brain, which occurs in Parkinson's disease and can start decades before any symptoms begin. Researchers also measured in 116 brains the amount of residue of a pesticide called heptachlor epoxide. The pesticide was found at very high levels in the milk supply in the early 1980s in Hawaii, where it was used in the pineapple industry. It was used to kill insects and was removed from use in the US around that time. The pesticide may also be found in well water.

The study found that nonsmokers who drank more than two cups of milk per day had 40 percent fewer brain cells in that area of the brain than people who drank less than two cups of milk per day. For those who were smokers at any point, there was no association between milk intake and loss of brain cells. Previous studies have shown that people who smoke have a lower risk of developing Parkinson's disease.

Residues of heptachlor epoxide were found in 90 percent of people who drank the most milk, compared to 63 percent of those who did not drink any milk. Abbott noted that the researchers do not have evidence that the milk participants drank contained heptachlor epoxide. He also stated that the study does not show that the pesticide or milk intake cause Parkinson's disease; it only shows an association.

"There are several possible explanations for the association, including chance," said Honglei Chen, MD, PhD, with the National Institute of Environmental Health Sciences and a member of the American Academy of Neurology, who wrote a corresponding editorial. "Also, milk consumption was measured only once at the start of the study, and we have to assume that this measurement represented participants' dietary habits over time."
Chen noted that the study is an excellent example of how epidemiological studies can contribute to the search for causes of Parkinson's disease.

This study was supported by the National Institute on Aging, the National Heart, Lung, and Blood Institute, the National Institute of Neurological Disorders and Stroke, the Department of the Army, the Department of Veterans Affairs, and the Kuakini Medical Center.

R. D. Abbott, G. W. Ross, H. Petrovitch, K. H. Masaki, L. J. Launer, J. S. Nelson, L. R. White, C. M. Tanner. Midlife milk consumption and substantia nigra neuron density at death. Neurology, 2015; DOI: 10.1212/WNL.0000000000002254

Human Breastmilk Is Protective During Infections, Study

          AsianScientist (May 27, 2013) – Breastfeeding is protective when there is an infection in mothers or babies due to the immune cells called leukocytes found in human breastmilk, says a new international study led by The University of Western Australia.
The research may help to explain why babies who are exclusively breastfed have fewer infections.
In a paper published in the journal Clinical and Translational Immunology, lead author UWA’s Assistant Professor Foteini Hassiotou and colleagues show how the number of leukocytes in breastmilk changes during the course of breastfeeding as well as in response to maternal and infant infection.
The team recruited 21 breastfeeding mothers and their babies at different stages of lactation, from a few days after birth to several years into lactation. The researchers first established the normal range of leukocytes in the milk of healthy mothers and babies.
They then found that the leukocytes in breastmilk increased rapidly when either the mother or her baby had an infection and returned to normal levels when the infection was over. Remarkably, this response was also seen when only the baby had an infection and the mother was asymptomatic, reinforcing the importance of breastfeeding for the protection of the baby.

“In places where families don’t have ready access to medicine, particularly developing countries, breastfeeding may be a determining factor in infant recovery and survival,” the study authors write.
“Formula doesn’t offer this protection and the ability to adjust to infant needs. These findings present new information that is relevant to updating public policy on early infant nutrition that maximizes immunological development and protection. At the same time, they offer new grounds for examining the mechanisms behind the very low rates of symptomatic HIV and cytomegalovirus disease in infants exclusively breastfed by infected mothers.”

The study also found that exclusive breastfeeding was associated with a higher baseline level of leukocytes in breastmilk under healthy conditions. This may be because of the overall suckling time on the breasts and suggests that babies that are not exclusively breastfed receive not only lower breastmilk volumes but also breastmilk that contains fewer leukocytes.
Assistant Professor Hassiotou and her colleagues point out that the human lactating breast is the only metabolically significant organ of the body for which a medical test does not exist – yet cow’s udders are often tested. The measurement of breastmilk leukocyte levels now provides a new diagnostic tool for the health of the lactating breast and of the breastfed infant.
The article can be found at: Hassiotou F et al. (2013) Maternal and infant infections stimulate a rapid leukocyte response in breastmilk.

Breast-milk stem cells may bypass ethical dilemmas

Embryonic-like stem cells have been isolated from breast milk in large numbers. The discovery raises the possibility of sourcing stem cells for regenerative medicine, without the need to destroy embryos.

Peter Hartmann at the University of Western Australia in Crawley and his colleagues first announced the discovery of stem cells in breast milk in 2008. Now they have grown them in the lab and shown that they can turn into cells representative of all three embryonic germ layers, called the endoderm, mesoderm and ectoderm – a defining property of embryonic stem cells (ESC).

"They can become bone cells, joint cells, fat cells, pancreatic cells that produce their own insulin, liver cells that produce albumin and also neuronal cells," says Foteini Hassiotou, a member of Hartmann's lab team, who led the recent work.

The breast cells also express the majority of protein markers that you would expect to find in ESCs. "What is really amazing is that these cells can be obtained in quite large amounts in breast milk," Hassiotou adds.

She says the stem cells constitute around 2 per cent of cells in breast milk although the number varies according to how long the woman has been producing milk and how full her breasts are. Hassiotou will present the team's work at the 7th International Breastfeeding and Lactation Symposium in Vienna, Austria early next year.

Many remain sceptical, however. "Perhaps there are some mammary gland stem cells that can be coaxed to have a slightly broader potential than normal, but I very much doubt that embryonic-like cells normally exist in the breast," says Robin Lovell-Badge of the National Institute for Medical Research in London. For one thing, you would expect tumours to be more common than they are.

The real test will be to inject these cells into mice and see if they form teratomas – tumours containing tissue or structures derived from all three germ layers. "That's the gold standard for whether you have a true pluripotent cell," says Chris Mason of University College London. Hassitou says they plan to start these tests in the coming weeks.

Embryonic-like stem cells have previously been discovered in amniotic fluid and in the umbilical cord, but this is the first time they have been discovered in an adult. Other adult stems cells exist – such as hematopoietic stem cells, which can generate all types of blood cell and mesenchymal stem cells, which can turn into bone, fat and cartilage cells. But these stem cells cannot generate as many cell types as the breast milk cells apparently can. "If they are truly embryonic, this would be another way of getting stem cells that would not raise ethical concerns," says Mason.

However, even if they do not turn out to be ESCs, these breast milk cells could still have great potential for regenerative medicine. "It might be possible to grow these cells in culture then bank them so that if or when the mother develops some disease later in life, such as diabetes, her cells may be defrosted and differentiated into pancreatic beta cells," says Lyle Armstrong of Newcastle University, UK, although he too, cautions that more tests are needed to determine exactly what these cells are.

The discovery also raises intriguing questions about the role of these cells in breastfed babies. "It has been shown in mice that live immune cells in breast milk pass through the intestinal mucosa into the blood circulation of the pups and engraft in various tissues," says Hassiotou. "If these cells are in human milk and in such high amounts they probably have a role. They might contribute to tissue regeneration and development of the baby or play certain roles if there is a disease."

The team is planning experiments to track what happens to these cells once they get into infants.

New Scientist: November 2011 by Linda Geddes

Lactose-free milk protein-based infant formula: impact on growth and gastrointestinal tolerance in infants

Abstract
Lactose, the major carbohydrate in human milk and standard milk-based formulas, provides energy for growth in infants. The use of lactose-free milk protein-based infant formulas has increased in the United States. However, clinical studies of their impact on growth, safety, and gastrointestinal tolerance in infants are limited. Thus, a prospective, blinded, randomized clinical trial was conducted in healthy, normal-term infants fed an experimental lactose-free milk protein-based formula (NoLAC; n = 63) versus a standard commercial lactose-containing milk-based formula (LAC; n = 65) for 112 days. Growth (weight, length, and head circumference) was similar and normal in both groups (weight gain: NoLAC = 31.1 ± 0.9 g/day, LAC = 29.4 ± 0.9 g/day, mean ± SEM; P = .895). Serum biochemistries for both groups were within infants' normal reference ranges. Both groups had comparable tolerance but the NoLAC group had softer stools and lower spit-ups. Thus, the study suggests that absence of lactose in milk-based formula does not adversely affect normal growth in term infants.

Lasekan JB, Jacobs J, Reisinger KS, Montalto MB, Frantz MP, Blatter MM.

Abbott Nutrition, Abbott Laboratories, Columbus, OH, USA,

Human breast milk is a rich source of multipotent mesenchymal stem cells

Abstract
Putative stem cells have been isolated from various tissue fluids such as synovial fluid, amniotic fluid, menstrual blood, etc. Recently the presence of nestin positive putative mammary stem cells has been reported in human breast milk. However, it is not clear whether they demonstrate multipotent nature. Since human breast milk is a non-invasive source of mammary stem cells, we were interested in examining the nature of these stem cells.

In this pursuit, we could succeed in isolating and expanding a mesenchymal stem cell-like population from human breast milk. These cultured cells were examined by immunofluorescent labeling and found positive for mesenchymal stem cell surface markers CD44, CD29, SCA-1 and negative for CD33, CD34, CD45, CD73 confirming their identity as mesenchymal stem cells. Cytoskeletal protein marker analysis revealed that these cells expressed mesenchymal stem cells markers, namely, nestin, vimentin, smooth muscle actin and also manifests presence of E-Cadherin, an epithelial to mesenchymal transition marker in their early passages.

Further we tested the multipotent differentiation potential of these cells and found that they can differentiate into adipogenic, chondrogenic and oesteogenic lineage under the influence of specific differentiation cocktails. This means that these mesenchymal stem cells isolated from human breast milk could potentially be “reprogrammed” to form many types of human tissues. The presence of multipotent stem cells in human milk suggests that breast milk could be an alternative source of stem cells for autologous stem cell therapy although the significance of these cells needs to be determined.

Satish PATKI1, Sachin KADAM2, Vikash CHANDRA2, Ramesh BHONDE2

Impact of breast milk on IQ, brain size and white matter development

Although observational findings linking breast milk to higher scores on cognitive tests may be confounded by factors associated with mothers' choice to breastfeed, it has been suggested that one or more constituents of breast milk facilitate cognitive development, particularly in preterms. Because cognitive scores are related to head size, we hypothesised that breast milk mediates cognitive effects by affecting brain growth.

We used detailed data from a randomized feeding trial to calculate percentage of breast milk (%EBM) in the infant diet of 50 adolescents. MRI scans were obtained (mean age=15y9m), allowing volumes of total brain (TBV), white and grey matter (WMV, GMV) to be calculated. In the total group %EBM correlated significantly with Verbal IQ (VIQ); in boys, with all IQ scores, TBV and WMV. VIQ was, in turn, correlated with WMV and, in boys only, additionally with TBV. No significant relationships were seen in girls or with grey matter.

These data support the hypothesis that breast milk promotes brain development, particularly white matter growth. The selective effect in males accords with animal and human evidence regarding gender effects of early diet. Our data have important neurobiological and public health implications and identify areas for future mechanistic study.

Infant sex predicts breast milk energy content

Camille E. Powe 1 *, Cheryl D. Knott 2, Nancy Conklin-Brittain 1


Abstract
During human evolutionary history, and for many around the world, breast milk is the primary source of nutritional energy for infants. Variation in breast milk quality might logically have important effects on infant health, growth, and development, yet the sources of this variation remain largely unelucidated. We quantified nutrient and energy content of breast milk from 25 healthy, well-nourished Massachusetts mothers with infants aged 2-5 months. We examined several potential sources of variation in milk quality, particularly feeding patterns, infant sex, and maternal breast growth during pregnancy.

After controlling for time since last feeding, a known correlate of milk composition, we found that mothers of male infants produced milk that had 25% greater energy content than mothers of female infants (P < 0.001). Change in maternal bra cup size during pregnancy was associated with 16.17 kcal/100 ml greater energy content of milk (P = 0.009), but was not significant after taking infant sex into account. Greater nutritional investment in sons may account for the greater observed growth rates in male compared to female infants.

Funded by:
Harvard College Research Program, Cambridge, Massachusetts
Camille E. Powe 1 *, Cheryl D. Knott 2, Nancy Conklin-Brittain 1
1Department of Anthropology, Harvard University, Cambridge, Massachusetts 02138
2Department of Anthropology, Boston University, Boston, Massachusetts 02115